An adiabatic cylinder has 8 gram of helium in it at 400 K and its piston of area $1c{m}^2$(which has mass 1 kg) is movable. If a block of mass 62 kg is placed on the piston then the final temperature of the gas will be $\left(n\times 100\right)K$ find the value of $n$ (Take atmospheric pressure to be ${10}^{5}N{m}^{-2}$ and $g=10m/s^2$ )